Agenda:
- Validation Harmonized Protocol: update - Validation vs pathology- Hippocampal Label Expansion project: update- News- Congress presentations- Papers
XVIII PMT meeting – June 5, 2013
Validation versus pathology
1 tracer (Greg)
Segmentation based on Harmonized Protocol:
Analysis based on the information available for each dataset and vs Bobinsky’s paper
Mayo ClinicAD + CTRL + MCI dataset
with pathologically confirmed diagnosis (Braak’s stages),
but not postmortem hippocampal measurement
Mony DeLeon15 AD + 5 CTRL at 1.5T
postmortem MRI and quantitative histology
(possible additional AD cases)
(Bobinsky paper on 9 AD+4 NL sbj scanned with Philips)
15 Philips + 18 GE13 post-mortem 10 post-m
T1 PD
50antem
de Leon
GE PD
Partial volume??
de Leon
Philips T1
Hippocampal Label Expansion project: update
Subjects = 135 Hippocampi = 270
MRI tracer tracing QC/correction Certification
68/68 1.5 T Masami Complete I-II Complete
(67 3T)30/30 Dominik Complete I-II Complete12/12 Rossana Complete I-II Complete10/10 Martina Complete I-II Complete15/15 Michel Complete I-II Complete
SD received all of the certified labels
Tracers are Masters or platform-Qualified. Anyway, exact ICCs across the 5 can be computed using the volumes of the Qualification round.
PLATFORM
- SD has tech support from PAVI, at Université de Sherbrooke
-They are looking into file formats for the contours
- SD has scheduled a meeting with the Technical Advisory group
Hippocampal Label Expansion project: SD update
News: Subfields
Group composed by Paul Yushkevich, Susan Mueller and Lei Wang aims to converge hippo-subfields imagers for protocol harmonization.
They asked for our participation, to tune the protocols and import harmonizaton methods.
We are invited to present the Hippo Harmonization project a-remoto to their HS3 meeting, June 21-2
http://hippos3.wordpress.com/
News: Duvernoy
Duvernoy explained some unclear anatomy issues and approved:
AC-PC standard orientation
Inclusion of “vestigial” tissue
Choices of the Delphi panel
Participation as a coauthor
NEXT HARMONIZATION MEETING: JULY 17 H 12-14
- AIC-AAIC (Boston, July 13-18, 2013) Training of Naïve Tracers; Statistics for Certification Platform POSTERS
- AIC-AAIC developing topicsValidation phase 1: preliminary data; Expansion project: preliminary data on 1.5T images
SUBMITTED
-CTAD (San Diego, Nov 3-5, 2011)Validation phase 1: preliminary data; Expansion project: preliminary data on 1.5T images
SUBMITTED
Congress Presentations
Papers
1) Survey of protocols (preliminary phase; JAD 2011)2) Operationalization (preliminary phase; Alzheimer’s &
Dementia, published online)3) Axes check short report (Brescia Team, ADJ-D-13-00030,
I revision)4) Master tracers’ practice and reliability (Brescia Team,
Sent to coauthors)
5) Development of certification platform (Duchesne and coll)6) Consensual Protocol definition (Brescia Team –
companion paper 1)
7) Validation data (Brescia Team – companion paper 2)8) Validation vs pathology (TBD)
DO
NE
ON
GO
ING
PL
AN
NE
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VALIDATION VS CURRENT PROTOCOLSASSESSMENT OF SOURCES OF
VARIANCE TRAINING SET DEVELOPMENT
VALIDATION VS PATHOLOGY
GOLD STANDARD
Harmonized ProtocolADNI scans: 2 x 5 Scheltens’s
atrophy score x 2 sides x 2 magnet strengths (1.5-3T)
Total per rater: 40 hippos
Harmonized ProtocolADNI scans: 2 sides x 5 Scheltens’s atrophy scores
x 3 time points (bl-1y-2y) x 3 scanners (+ retracing @ bl)
x 2 magnet strengths (1.5-3T)Total per rater: 240 hippos
Assessment of variance due to rater and center
Local ProtocolADNI scans: 2 x 5 Scheltens’s atrophy scores
x 2 sides x 2 magnet strengths (1.5-3T)
Harmonized ProtocolADNI scans: 2 x 5 Scheltens’s atrophy score x
2 sides x 2 magnet strength (1.5-3T)Total per rater: 40 hippos Harmonized Protocol:
Pathological datasets: Mayo Clinic and NYU
Total: about 40 hippos
TrainingADNI scans: 10 at 1.5T x 2 sides x 7
SUs x 2 tracing roundsTotal per rater: 40 hippos
20 naïve tracers 5 master tracers 1 tracer
REFERENCE PROBABILISTIC MASKS
with 95% C.I.
QUALIFICATION QUALIFICATION
Best 5 naïve tracers
Assessment of variance due to side, trace-retrace, atrophy, time, scanner, rater
TRAINING SET
Assessment of agreement with volume on pathology or ex vivo
MRI and correlation with neuronal density
GANTT